I see.
I think of erosion as being caused by physical contact ...........
Like how water erodes a hillside.
Corrosion involves a chemical process rather than a physical process of
digging away at something. 
When you say 'technically speaking' ............then it could mean more than
the normal way we use these words.  Most words have numerous definitions if
you look them up. 

-----Original Message-----
From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com] On Behalf Of
Mike
Sent: Wednesday, February 20, 2008 1:31 PM
To: vanagon@GERRY.VANAGON.COM
Subject: Re: Electric Water Pump

I was taught in Aviation mechanic school that technically-speaking erosion
is a form of corrosion..........."Corrosion" encompasses many types of
breakdown processes.

Mike B.

> Yes corrosion and erosion are different things. Both can be a problem. So
> can cylinder liner cavitations erosion. This is a particular problem on
> Diesels. Just ask Ford power Stroke owners that have replaced engines.